If you preview the projection query, it seems to work, so don't press preview

The error on a page is below (the Original error from the poster only appears in the admin site)

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
Source Error:

Line 205:
Line 206: // allocate instance and set record property
Line 207: contentItem = New(versionRecord.ContentItemRecord.ContentType.Name);
Line 208: contentItem.VersionRecord = versionRecord;
Line 209: